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1.
Development ; 147(20)2020 10 23.
Artigo em Inglês | MEDLINE | ID: mdl-33097549

RESUMO

Vitellogenesis, including vitellogenin (Vg) production in the fat body and Vg uptake by maturing oocytes, is of great importance for the successful reproduction of adult females. The endocrinal and nutritional regulation of vitellogenesis differs distinctly in insects. Here, the complex crosstalk between juvenile hormone (JH) and the two nutrient sensors insulin/IGF signaling (IIS) and target of rapamycin complex1 (TORC1), was investigated to elucidate the molecular mechanisms of vitellogenesis regulation in the American cockroach, Periplaneta americana Our data showed that a block of JH biosynthesis or JH action arrested vitellogenesis, in part by inhibiting the expression of doublesex (Dsx), a key transcription factor gene involved in the sex determination cascade. Depletion of IIS or TORC1 blocked both JH biosynthesis and vitellogenesis. Importantly, the JH analog methoprene, but not bovine insulin (to restore IIS) and amino acids (to restore TORC1 activity), restored vitellogenesis in the neck-ligated (IIS-, TORC1- and JH-deficient) and rapamycin-treated (TORC1- and JH-deficient) cockroaches. Combining classic physiology with modern molecular techniques, we have demonstrated that IIS and TORC1 promote vitellogenesis, mainly via inducing JH biosynthesis in the American cockroach.


Assuntos
Proteínas de Insetos/metabolismo , Fator de Crescimento Insulin-Like I/metabolismo , Insulina/metabolismo , Hormônios Juvenis/biossíntese , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Periplaneta/metabolismo , Transdução de Sinais , Vitelogênese , Animais , Feminino , Metoprene/farmacologia , Folículo Ovariano/metabolismo , Sirolimo/farmacologia , Vitelogeninas/biossíntese
2.
Insect Mol Biol ; 32(1): 46-55, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36214335

RESUMO

Insects are the most widely distributed and successful animals on the planet. A large number of insects are capable of flight with functional wings. Wing expansion is an important process for insects to achieve functional wings after eclosion and healthy genital morphology is crucial for adult reproduction. Myofilaments are functional units that constitute sarcomeres and trigger muscle contraction. Here, we identified four myofilament proteins, including Myosin, Paramyosin, Tropomyosin and Troponin T, from the wing pads of nymphs in the American cockroach, Periplaneta americana. RNAi-mediated knockdown of Myosin, Paramyosin, Tropomyosin and Troponin T in the early stage of final instar nymphs caused a severely curly wing phenotype in the imaginal moult, especially in the Paramyosin and Troponin T knockdown groups, indicating that these myofilament proteins are involved in controlling wing expansion behaviours during the nymph-adult transition. In addition, the knockdown resulted in abnormal external genitalia, caused ovulation failure, and affected male accessory gland development. Interestingly, the expression of myofilament genes was induced by methoprene, a juvenile hormone (JH) analogue, and decreased by the depletion of the JH receptor gene Met. Altogether, we have determined that myofilament genes play an important role in promoting wing expansion and maintaining adult genitalia morphology, and their expression is induced by JH signalling. Our data reveal a novel mechanism by which wing expansion is regulated by myofilaments and the functions of myofilaments are involved in maintaining genitalia morphology.


Assuntos
Periplaneta , Feminino , Masculino , Animais , Periplaneta/genética , Periplaneta/metabolismo , Miofibrilas , Tropomiosina/genética , Tropomiosina/metabolismo , Troponina T/metabolismo , Metamorfose Biológica , Insetos , Hormônios Juvenis/metabolismo , Ninfa
3.
Appl Opt ; 57(19): 5258, 2018 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-30117813

RESUMO

This publisher's note corrects the author listing and a figure caption in Appl. Opt.57, 3481 (2018)APOPAI0003-693510.1364/AO.57.003481.

4.
Appl Opt ; 57(13): 3481-3487, 2018 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-29726517

RESUMO

Chinese hybrid rice of different varieties, growing in paddies in the Pingqiao district, north of Xinyang city, Henan province, China, was studied in detailed spectroscopic characteristics using laser-induced fluorescence. The base for the studies was the new South China Normal University mobile lidar laboratory, which was dispatched on site, providing facilities both for laboratory studies using a 405 nm excitation source as well as remote sensing measurements at ranges from around 40 m-120 m, mostly employing the 532 nm output from a Nd:YAG laser. We, in particular, studied the spectral influence of the species varieties as well as the level of nitrogen fertilization supplied. Specially developed contrast functions as well as multivariate techniques with principal components and Fisher's discriminate analyses were applied, and useful characterization of the rice could be achieved. The chlorophyll content mapping of the 30 zones was obtained with the remote sensing measurements.


Assuntos
Clorofila/análise , Fluorescência , Lasers de Estado Sólido , Nitrogênio/análise , Oryza/química , Tecnologia de Sensoriamento Remoto/métodos , Espectrometria de Fluorescência , China , Oryza/genética
5.
Opt Express ; 24(6): A515-27, 2016 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-27136872

RESUMO

Laser spectroscopy provides many possibilities for multi-disciplinary applications in environmental monitoring, in the ecological field, for food safety investigations, and in biomedicine. The paper gives several examples of the power of multi-disciplinary applications of laser spectroscopy as pursued in our research group. The studies utilize mostly similar and widely applicable spectroscopic approaches. Air pollution and vegetation monitoring by lidar techniques, as well as agricultural pest insect monitoring and classification by elastic scattering and fluorescence spectroscopy are described. Biomedical aspects include food safety applications and medical diagnostics of sinusitis and otitis, with strong connection to the abatement of antibiotics resistance development.


Assuntos
Pesquisa Biomédica , Inocuidade dos Alimentos , Lasers , Espectrometria de Fluorescência , Farmacorresistência Bacteriana , Ecologia , Humanos , Otite/diagnóstico por imagem , Sinusite/diagnóstico por imagem
6.
Insect Sci ; 31(1): 186-200, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37327125

RESUMO

Reproduction is of great importance for the continuation of the species. In insects, the fat body is the major tissue for nutrient storage and involved in vitellogenesis, which is essential for female reproduction. Here, 2 proteins, hexamerin and allergen, were separated from the fat bodies of adult female American cockroaches (Periplaneta americana) and identified as storage proteins, encoding for 733 amino acids with molecular weight of 87.88 kDa and 686 amino acids with molecular weight of 82.18 kDa, respectively. The encoding genes of these 2 storage proteins are mainly expressed in the fat body. RNA interference-mediated knockdown of Hexamerin and Allergen in the early stage of the first reproductive cycle in females suppressed vitellogenesis and ovarian maturation, indicating that these storage proteins are involved in controlling reproduction. Importantly, the expression of Hexamerin and Allergen was repressed by knockdown of the juvenile hormone (JH) receptor gene Met and the primary response gene Kr-h1, and was induced by methoprene, a JH analog, in both in vivo and in vitro experiments. Altogether, we have determined that hexamerin and allergen are identified as storage proteins and play an important role in promoting female reproduction in the American cockroach. The expression of their encoding genes is induced by JH signaling. Our data reveal a novel mechanism by which hexamerin and allergen are necessary for JH-stimulated female reproduction.


Assuntos
Periplaneta , Feminino , Animais , Periplaneta/metabolismo , Alérgenos/metabolismo , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Hormônios Juvenis/metabolismo , Vitelogênese , Aminoácidos/metabolismo , Reprodução
7.
Int J Biol Macromol ; 230: 123177, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36623615

RESUMO

EPS53, a homogeneous exopolysaccharide (EPS) was isolated from Streptococcus thermophiles XJ53 fermented in skimmed milk via anion exchange column chromatography. The relative molecular weight of EPS53 was above 6.7 × 105 g/mol; its repeating structural unit of EPS53 consisted of ß-T-Galp, ß-1,3-Galf, α-1,3-Glcp and ß-1,3,6-Glcp residues in a molar ratio of 1:1:1:1, with ß-T-Galp attached to the O-6 position of ß-1,3,6-Glcp,identical to the EPS produced from S. thermophilus SFi39. EPS53-D, purified under similar conditions as EPS53 except for the deproteinization of trichloroacetic acid (TCA), had a lower molecular weight but the same repeating structural unit. The effects of EPS53 and EPS53-D on proliferation, phagocytosis and nitric oxide (NO) release of macrophage RAW264.7 were compared. EPS53 exhibited stronger immune activity than EPS53-D, suggesting that the molecular weight might have an important effect on the activity of EPS molecules. Treatment with TCA might affect the activities of native EPSs produced by fermentation.


Assuntos
Polissacarídeos Bacterianos , Streptococcus thermophilus , Streptococcus thermophilus/química , Peso Molecular , Polissacarídeos Bacterianos/farmacologia , Polissacarídeos Bacterianos/química , Macrófagos , Fagocitose
8.
Nat Commun ; 14(1): 8234, 2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-38086980

RESUMO

DNA methylation at the fifth position of cytosine (5-methylcytosine, 5mC) is a crucial epigenetic modification for regulating gene expression, but little is known about how it regulates gene expression in insects. Here, we pursue the detailed molecular mechanism by which DNMT1-mediated 5mC maintenance regulates female reproduction in the German cockroach, Blattella germanica. Our results show that Dnmt1 knockdown decreases the level of 5mC in the ovary, upregulating numerous genes during choriogenesis, especially the transcription factor ftz-f1. The hypomethylation at the ftz-f1 promoter region increases and prolongs ftz-f1 expression in ovarian follicle cells during choriogenesis, which consequently causes aberrantly high levels of 20-hydroxyecdysone and excessively upregulates the extracellular matrix remodeling gene Mmp1. These changes further impair choriogenesis and disrupt fertilization by causing anoikis of the follicle cells, a shortage of chorion proteins, and malformation of the sponge-like bodies. This study significantly advances our understanding of how DNA 5mC modification regulates female reproduction in insects.


Assuntos
Proteínas de Ligação a DNA , Fatores de Transcrição , Animais , Feminino , Proteínas de Ligação a DNA/metabolismo , Fatores de Transcrição/metabolismo , Regulação da Expressão Gênica , Insetos/metabolismo , Fertilização/genética
9.
Heart Lung ; 51: 25-31, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34731694

RESUMO

This article has been withdrawn at the request of the author(s) and/or editor. The Publisher apologizes for any inconvenience this may cause. The full Elsevier Policy on Article Withdrawal can be found at http://www.elsevier.com/locate/withdrawalpolicy.

10.
Carbohydr Polym ; 282: 119103, 2022 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-35123741

RESUMO

A novel exopolysaccharide named BD0.4 was purified from the fermentation broth of Paenibacillus bovis sp. nov BD3526 in wheat bran medium via anion exchange column chromatography. Its fine structure was identified by a variety of physical and chemical methods. BD0.4, with the weight average molecular weight of 376 kDa, consisted of glucuronic acid, glucose and fucose in a molar ratio of 1.58:1:1.66. The backbone included 1,3-linked Fuc, 1,3,4-linked Fuc, 1,3-linked Glc and 1,4-linked GlcA residues, with the branching point located at the O4 position of 1,3,4-linked Fuc residues, and the branched chain composed of terminal GlcA residues. BD0.4 could improve the phagocytic ability of macrophages and significantly stimulate the secretion of NO, TNF-α, IL-1ß and IL-6 from RAW264.7 cells in a dose-dependent manner. BD0.4 could promote the expression of NF-кB and cause nuclear translocation of NF-κB p65, indicating that BD0.4 probably exerted immune activity through the NF-κB signaling pathway.


Assuntos
Paenibacillus , Polissacarídeos Bacterianos/química , Polissacarídeos Bacterianos/farmacologia , Animais , Citocinas/metabolismo , Metilação , Camundongos , Estrutura Molecular , NF-kappa B/metabolismo , Óxido Nítrico/metabolismo , Fagocitose/efeitos dos fármacos , Células RAW 264.7 , Ácidos Urônicos/química
11.
Insect Sci ; 28(2): 485-494, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32174010

RESUMO

The transcription factor grainy head (Grh) functions in the protection of the epithelium against the external environment by generating strongly adhesive layers, and this function is conserved in vertebrates and invertebrates. In Drosophila, the top model for holometabolous insects, Grh is necessary during embryonic development, epidermal differentiation, central nervous system specification and epithelial repair. However, the function of this gene in hemimetabolous insect epithelia remains unknown. To examine the function of Grh signaling in regulating epithelium development in Hemimetabola, we focused on the Blattella germanica epidermal layer using a gene knockdown strategy. The spatiotemporal expression pattern of BgGrh was detected, and knockdown of BgGrh and BgCad96ca, which provide positive feedback to BgGrh, caused severe defects in new epithelium development and impeded the molting process required to discard the old integument. Knockdown of the expression of BgGrh and BgCad96ca caused increased expression of chitin synthase gene (BgCHS1) and chitinase gene (BgCht5), the upregulations of which should be mediated by the higher level of hormone receptor 3 (BgHr3) gene. In conclusion, epithelium development is regulated by Grh signaling, which might represent a potential target for the control of urban pest cockroaches.


Assuntos
Blattellidae/crescimento & desenvolvimento , Epitélio/crescimento & desenvolvimento , Proteínas de Insetos/genética , Muda/genética , Animais , Blattellidae/genética , Proteínas de Insetos/metabolismo , Ninfa/genética , Ninfa/crescimento & desenvolvimento
12.
Sci Rep ; 10(1): 10414, 2020 06 26.
Artigo em Inglês | MEDLINE | ID: mdl-32591617

RESUMO

Mercury is, because of its high vapor pressure and its prevalence in the atmosphere as atoms, an interesting geophysical tracer gas, also with potential archaeological applications. According to historical records dating back 2200 years, the mausoleum chamber of the "Terracotta Army Emperor" Qin in Xi´an, China, contains large amounts of liquid mercury, considered as an elixir of life at the time. We here report on measurements of the atmospheric contents of atomic mercury above the tomb mound performed with a mobile differential absorption lidar (light detection and ranging) system. Our measurements, which were performed from three different locations around the mound, indeed indicate elevated atmospheric mercury levels, with localizations, which correlate with previous in situ soil sampling results. Concentrations up to 27 ng/m3 were observed, significantly higher than the typical general pollutant level in the area which was found to be around 5-10 ng/m3. An out-flux of about 5×10-8 kg/s was estimated. Highly volatile mercury may be escaping through cracks, which developed in the structure over time, and our investigation supports ancient chronicle records on the tomb, which is believed never to have been opened/looted. Our findings also have bearings on the proposed use of mercury as a tracer gas for valuable ores and geothermal resource exploration, and also bring problematics around reliable nuclear waste long-term underground storage to mind.

13.
J Insect Physiol ; 118: 103934, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31449796

RESUMO

In insects, nutrition and hormones coordinately regulate lifespan and reproduction, which might affect each other. We here investigated how nutrition, insulin, and juvenile hormone (JH) signal genes affect lifespan and reproduction in the German cockroach, Blattella germanica, a serious urban pest throughout the world. Starvation as well as altering insulin and nutrition signal genes by RNA interference (RNAi) knockdown of the expression of either positive or negative components in the two pathways simultaneously reduced lifespan and ootheca number of the mated female cockroaches. Meanwhile, depletion of the JH receptor Methoprene-tolerant (Met), but not kruppel homolog 1 (Kr-h1) that predominately transduces JH signaling to prevent metamorphosis, significantly reduced the two parameters. Moreover, suppressing the expression of several reproduction-related genes, including doublesex (Dsx), vitellogenin (Vg), and the Vg receptor (VgR), had little yet various effects on lifespan; nevertheless, it is likely that there are some reproduction-independent mating factors reducing lifespan. In conclusion, through blocking lifespan and reproduction in a simultaneous manner, the alteration of insulin and nutrient signal gene expression or the depletion of Met might provide a great potential for controlling the German cockroach.


Assuntos
Blattellidae/genética , Blattellidae/metabolismo , Hormônios Juvenis/genética , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Feminino , Proteínas de Insetos/genética , Insulina/genética , Insulina/metabolismo , Hormônios Juvenis/metabolismo , Fatores de Transcrição Kruppel-Like/genética , Longevidade/genética , Metamorfose Biológica , Interferência de RNA , Reprodução
14.
R Soc Open Sci ; 6(10): 191132, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31824720

RESUMO

Nitrogen is one of the most important nutrient indicators for the growth of crops, and is closely related to the chlorophyll content of leaves and thus influences the photosynthetic ability of the crops. In this study, five hybrid rice varieties were cultivated during one entire growing period in one experimental field supplied with six nitrogen fertilizer levels. Visible and near infrared (vis/NIR) reflectance spectroscopy combined with multivariate analysis was used to identify hybrid rice varieties and nitrogen fertilizer levels, as well as to detect chlorophyll content associated with nitrogen levels. The support vector machine (SVM) algorithm was applied to identify five varieties of hybrid rice and six levels of nitrogen fertilizer. The results demonstrated that different varieties of hybrid rice for each nitrogen level can be well distinguished except for the highest nitrogen level, and no nitrogen level for each rice variety can be completely identified from the other five nitrogen levels. Further, 12 spectral indices combined with partial least square (PLS) analysis were applied for estimating chlorophyll content of rice leaves from plants subjected to different nitrogen levels, and a root mean square error of cross-validation (RMSECV) of 0.506, a coefficient of determination (R 2) of 97.8% and a ratio of performance to deviation (RPD) of 4.6 for all rice varieties indicated this as a preferable procedure. This study demonstrates that Vis/NIR spectroscopy can have a great potential for identification of rice varieties and evaluation of nitrogen fertilizer levels.

15.
Nephrol Dial Transplant ; 23(9): 2841-6, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18390891

RESUMO

BACKGROUND: Evidence suggests that transforming growth factor-beta1 (TGF-beta(1)) is associated with target organ damage in hypertension. This study aimed to investigate the relationship between TGF-beta(1) levels and kidney damage and renoprotective effects of angiotensin-converting enzyme inhibitor and/or angiotensin II type 1 receptor blocker in patients with essential hypertension (EH). METHODS: A total of 156 patients with EH were enrolled and grouped according to albumin-to-creatinine ratio (ACR). Of these, 90 patients with EH underwent a 12-week antihypertensive trial with administration of benazepril, valsartan or both. Serum TGF-beta(1), plasma angiotensin (Ang) II and urinary albumin were quantified by immunoassays. RESULTS: Serum TGF-beta1, plasma Ang II and ACR were highly elevated in patients with EH (P < 0.01). There was a positive correlation between serum TGF-beta1 levels and ACR (r = 0.53, P < 0.01). Significant decreases in TGF beta1 and ACR were obtained in all groups at the end of 12-week antihypertensive therapy compared to the baseline values, with the combined group to a greater extent (P < 0.01). Plasma Ang II levels were significantly decreased in the benazepril group but increased in the valsartan group (P < 0.05) while no significant change was observed in the combined group. CONCLUSIONS: TGF-beta(1) is highly elevated and strongly associated with urinary albumin excretion in patients with EH. Treatment with benazepril or valsartan attenuates serum TGF-beta(1) levels and microalbuminuria with the combined therapy receiving the greater effect. TGF-beta(1) could be a potential surrogate marker in monitoring the development and progression of kidney damage in EH.


Assuntos
Bloqueadores do Receptor Tipo 1 de Angiotensina II/farmacologia , Inibidores da Enzima Conversora de Angiotensina/farmacologia , Benzazepinas/farmacologia , Hipertensão/sangue , Rim/efeitos dos fármacos , Tetrazóis/farmacologia , Valina/análogos & derivados , Administração por Inalação , Angiotensina II/sangue , Bloqueadores do Receptor Tipo 1 de Angiotensina II/uso terapêutico , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Benzazepinas/uso terapêutico , Método Duplo-Cego , Feminino , Humanos , Hipertensão/urina , Nefropatias/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Tetrazóis/uso terapêutico , Fator de Crescimento Transformador beta1 , Valina/farmacologia , Valina/uso terapêutico , Valsartana
16.
J Card Surg ; 23(6): 681-7, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18778302

RESUMO

BACKGROUND: Determination of cardiac markers can assess cardiac injury induced by cardiopulmonary bypass (CPB) during coronary artery bypass grafting (CABG). However, the markers and their release pattern are not well defined. This study was aimed at assessing the release and timing of cardiac biochemical and inflammatory markers in patients undergoing elective CABG with CPB. METHODS: Forty patients undergoing elective CABG were included in this study. Blood samples were collected for biochemical measurements at the following time points: immediately prior to the induction of anesthesia, one, six, 12, and 24 hours after initiation of CPB. RESULTS: Increased release of cardiac troponin I was observed one hour after initiation of CPB (p < 0.05) and reached the maximum at 12 hours after CPB (p < 0.01). Serum CK-MB enzyme activity and CK-MB mass both were highly elevated starting at one hour after initiation of CPB, peaked at six hours, and remained elevated until 24 hours after CPB. Both lactate and lactate dehydrogenase were highly elevated six hours after CPB and peaked at 12 hours after CPB (p < 0.01). Serum levels of interleukin-6 and tumor necrosis factor-alpha increased significantly one hour after initiation of CPB and peaked at six hours (p < 0.01), while serum high sensitivity C-reactive protein levels started to elevate 12 hours after CPB (p < 0.01). CONCLUSION: Monitoring of these markers could help to determine implementation of protective interventions during CABG with CPB to prevent myocardial deterioration and to predict the risk and prognosis.


Assuntos
Ponte de Artéria Coronária/efeitos adversos , Inflamação/metabolismo , Adulto , Idoso , Biomarcadores/sangue , Proteína C-Reativa/metabolismo , Ponte Cardiopulmonar , Estudos de Coortes , Ponte de Artéria Coronária/métodos , Creatina Quinase Forma MB/sangue , Feminino , Humanos , Inflamação/etiologia , Interleucina-6/sangue , L-Lactato Desidrogenase/sangue , L-Lactato Desidrogenase/metabolismo , Ácido Láctico/sangue , Ácido Láctico/metabolismo , Masculino , Pessoa de Meia-Idade , Estresse Oxidativo , Estudos Prospectivos , Troponina I/sangue , Fator de Necrose Tumoral alfa/sangue , Fator de Necrose Tumoral alfa/metabolismo
17.
R Soc Open Sci ; 5(4): 172303, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29765679

RESUMO

We present the results of, to our knowledge, the first Lidar study applied to continuous and simultaneous monitoring of aerial insects, bats and birds. It illustrates how common patterns of flight activity, e.g. insect swarming around twilight, depend on predation risk and other constraints acting on the faunal components. Flight activity was monitored over a rice field in China during one week in July 2016, using a high-resolution Scheimpflug Lidar system. The monitored Lidar transect was about 520 m long and covered approximately 2.5 m3. The observed biomass spectrum was bimodal, and targets were separated into insects and vertebrates in a categorization supported by visual observations. Peak flight activity occurred at dusk and dawn, with a 37 min time difference between the bat and insect peaks. Hence, bats started to feed in declining insect activity after dusk and stopped before the rise in activity before dawn. A similar time difference between insects and birds may have occurred, but it was not obvious, perhaps because birds were relatively scarce. Our observations are consistent with the hypothesis that flight activity of bats is constrained by predation in bright light, and that crepuscular insects exploit this constraint by swarming near to sunset/sunrise to minimize predation from bats.

18.
Environ Pollut ; 240: 353-358, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29751331

RESUMO

A novel mobile laser radar system was used for mapping gaseous atomic mercury (Hg0) atmospheric pollution in the Wanshan district, south of Tongren City, Guizhou Province, China. This area is heavily impacted by legacy mercury from now abandoned mining activities. Differential absorption lidar measurements were supplemented by localized point monitoring using a Lumex RA-915M Zeeman modulation mercury analyzer. Range-resolved concentration measurements in different directions were performed. Concentrations in the lower atmospheric layers often exceeded levels of 100 ng/m3 for March conditions with temperature ranging from 5 °C to 20 °C. A flux measurement of Hg0 over a vertical cross section of 0.12 km2 resulted in about 29 g/h. Vertical lidar sounding at night revealed quickly falling Hg0 concentrations with height. This is the first lidar mapping demonstration in a heavily mercury-polluted area in China, illustrating the lidar potential in complementing point monitors.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental/métodos , Mercúrio/análise , Atmosfera/química , China , Poluição Ambiental , Mineração , Tecnologia de Sensoriamento Remoto
19.
Nat Commun ; 9(1): 1008, 2018 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-29559629

RESUMO

Many cockroach species have adapted to urban environments, and some have been serious pests of public health in the tropics and subtropics. Here, we present the 3.38-Gb genome and a consensus gene set of the American cockroach, Periplaneta americana. We report insights from both genomic and functional investigations into the underlying basis of its adaptation to urban environments and developmental plasticity. In comparison with other insects, expansions of gene families in P. americana exist for most core gene families likely associated with environmental adaptation, such as chemoreception and detoxification. Multiple pathways regulating metamorphic development are well conserved, and RNAi experiments inform on key roles of 20-hydroxyecdysone, juvenile hormone, insulin, and decapentaplegic signals in regulating plasticity. Our analyses reveal a high level of sequence identity in genes between the American cockroach and two termite species, advancing it as a valuable model to study the evolutionary relationships between cockroaches and termites.


Assuntos
Adaptação Biológica/fisiologia , Genoma , Genômica , Metamorfose Biológica/fisiologia , Periplaneta/fisiologia , Animais , Ecdisterona/fisiologia , Meio Ambiente , Feminino , Proteínas de Insetos/fisiologia , Insulina/fisiologia , Isópteros/genética , Hormônios Juvenis/fisiologia , Masculino , Filogenia , Interferência de RNA , Transdução de Sinais/fisiologia , Transcriptoma , Sequenciamento Completo do Genoma
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